To estimate a maximum purchase price for the coin in question, we can analyze the provided data:

1. Current Condition: The coin has a condition of 70 (MBC-), indicating that it is in an acceptable state, but not of high quality.

2. Auction History:
- The average hammer price for coins of similar condition (70) has been 37 euros (considering the auctions on 2020-02-12 and 2018-04-24).
- In previous auctions, hammer prices have varied, but there are examples of sales in the range of 9 to 650 euros, depending on the condition and other factors.

3. Average Starting and Hammer Price:
- The average starting price is 56.88 euros and the average hammer price is 94.71 euros. This suggests that, in general, coins of this reference tend to sell for a price higher than the starting price.

4. Recent Trends: In the most recent auctions, hammer prices have shown a trend of being higher, especially for coins in better condition.

5. Estimation: Given that the condition of the coin is 70 and considering the hammer price history, an estimated maximum purchase price could be in the range of 40 to 60 euros, taking into account that the average hammer price for similar conditions has been approximately 37 euros.

Therefore, an estimated maximum purchase price for this coin could be 60 euros.